He proposed that energy levels of electrons are discrete and that the electrons revolve in stable orbits around the atomic nucleus but can jump from one energy level (or orbit) to another.
Answer:
Study the bone structure of limbs.
Explanation:
Study the bone structure of limbs can be used to find out the relatedness and relationship among three species because the pattern of bones structure is similar but the structure is different from one another due to different environmental conditions. This study provides important and useful information whether the three species are closely related or not. If they have similar bone structure than we can say that there are more chances that they are closely related to each other.
1s^2 2s^2 2p^6 for the Mg2+ ion.
